The researchers take advantage of the fact that glass becomes viscous and malleable when exposed to high temperatures with, ‘precise calculations and gravity’ reportedly doing the rest.
The technique sees 4mm thick glass sheets put in an oven at just under the heat required to soften them. Here, a laser beam is then directed by adjustable mirrors, which heats across a pre-programmed path. The extra heat from the laser then causes parts of the glass to achieve the new and desired form.
This technique allows architects and industrial designers to make use of shapes that were previously difficult and costly to produce. Here, sheet glass is shaped without the need for a bending mould, meaning the process doesn’t leave behind any unsightly marks and the flat glass surface remain visually undistorted.
Tobias Rist, a scientist at Fraunhofer IWM, says: “Thanks to our technique, manufacturers have a cost-effective way of producing extremely customised glass objects in small batches or even as one-offs.”
Since the glass is removed for cooling, the bending oven is free for the next workpiece and so doesn’t have to be cooled down. This offers greater energy efficiency than conventional processes. While the laser requires a lot of energy, the very short processing times and the fact that it is fixed, save electricity.
The researchers are able to process sheet glass with edges of up to 1m and alter both sides of the glass. Next, they will experiment with different types of glass and explore further manufacturing variations with a view to expanding the range of shapes products can take.